1. Field of the Invention
This invention relates to a process for dyeing textile fabric. More particularly, the process relates to forming a dye image of a sublimable dye by magnetic printing, and transferring the dye image to a film of polymeric material through which the dye can sublime and then transferring the dye to a textile fabric by sublimation thereof.
2. Description of the Prior Art
In the conventional printing of textiles, normally the fabric is adhered to a printing blanket that transports it under the printing roll screens. After all colors have been applied, the fabric goes through oven drying, then the dyes are fixed, e.g., by hot air or high pressure and high temperature steam. The textiles are then scoured and dried. In structurally unstable fabrics, such as double knits, waste, due to inadequate registration of the different colors, in some cases may amount to 20 to 30% of the printed textile.
Magnetic printing processes, particularly useful in overcoming the problem in electrostatic copying processes of unsatisfactory copying of large dark areas, are known in the art. Such processes are described, for instance, in U.S. Pat. Nos. 4,099,186 and 4,117,498. The particular processes described in U.S. Pat. Nos. 4,099,186 and 4,117,498 relate to processes wherein a dye and/or other chemical treating agent contained in a ferromagnetic toner is transferred directly to a substrate e.g., such as a textile material, or is transferred to a first substrate such as paper for subsequent transfer to the ultimate substrate.
U.S. Pat. No. 3,860,388 describes a method of dye absorption into the surfaces of plastics by placing a polyethylene film between a dye transfer paper and a sheet of plastic and applying pressure and heat thereto. The dyes sublime through the polyethylene film to the plastic film to be dyed.
U.S. Pat. No. 3,915,628 relates to a continuous dry transfer-printing process for textile webs wherein a continuous inert carrier, advantageously stainless steel, aluminum or paper, is applied to the surface of the web, which is then contacted with the material to which the dye is to be transferred followed by heating and sublimation of the dye.